The invention relates to a cassette for a record carrier in the form of a tape, having two rotatable winding reels for taking up and unwinding the record carrier, and a spring-loaded brake lever for each of the winding reels, which lever is movable between a disengaged position, in which the brake lever is disengaged from the associated winding reel, and a braking position, in which the brake lever cooperates with the associated winding reel so as to brake said reel, the brake lever rotating the associated winding reel through a limited angle in a winding direction. A magnetic tape cassette of this type is known from U.S. Pat. No. 4,022,401.
In the known magnetic tape cassette the two brake levers are pivotably journalled on bearing pins which are rigidly mounted on two walls of the cassette, and the two brake levers each have a resilient hook at one of their ends, arranged to engage a toothed ring on the associated winding reel. The hooks are resilient so that as they engage the teeth when the two brake levers pivot to their braking positions, the two winding reels are slightly rotated in their winding directions as a result, after a cassette has been used any slackness in a span of the magnetic tape between the two rolls contained on the winding reels is eliminated, and the span extending between the two winding reels in the cassette is kept free from backlash and is taut under the influence of a comparatively small tensile force. This is essential for a correct operation of the cassette, because if the magnetic tape in the cassette is not taut, the tape is likely to be damaged when the cassette is placed on or is removed from a magnetic tape apparatus.
Because the two brake levers are journalled on fixed pins and the space inside the cassette is limited in order to accommodate a maximum amount of magnetic tape, the lever arms of the brake lever also have limited dimensions, and the travel of the resilient hooks of the brake levers is limited. Consequently, only comparatively small rotary movements of the two winding reels are possible, so that in the known cassette only a slight degree of slackness of the magnetic tape can be eliminated. Thus, with the known cassette it is not always ensured that the magnetic tape is taut under all conditions.